Method and apparatus for coiling strip

ABSTRACT

IN UNCOILING AN OPEN COIL OF STEEL STRIP ARRANGED WITH ITS AXIS VERTICAL AND RECOILING THE STRIP INTO A TIGHT COIL ALSO ARRANGED WITH ITS AXIS VERTICAL, THE STRIP PASSES AROUND A VERTICAL TENSION DRUM WITH A VERTICAL SNUBBER ROLL BEARING AGAINST THE STRIP ON THE TENSION DRUM IN ORDER TO POSITION THE STRIP IN A DESIRED VERTICAL POSITION. THE SNUBBER ROLL HAS A SPLINE CONNECTION WITH A ROTATABLE SHAFT FIXED IN A VERTICAL POSITION. MOVEMENT OF THE STRIP CAUSES ROTATION OF THE SNUBBER ROLL AND ITS SHAFT. THE SNUBBER ROLL IS CONNECTED   TO TWO DIAMETRICALLY OPPOSED NUTS WHICH ENGAGE VERTICAL THREADED GUIDE RODS WHICH ARE ROTATED IN UNISON BY A REVERSIBLE MOTOR. IF THE STRIP WANDERS FROM ITS DESIRED POSITION THE OPERATOR RUNS THE MOTOR IN THE DESIRED POSITION TO RAISE OR LOWER THE SNUBBER ROLL WHILE THE COILING CONTINUES TO RETURN THE STRIP TO THE DESIRED POSITION.

INVENTOR 4, L.-J.`JOHNSON METHOD AND" APPARATUS Fon coILING Y STRIP "Filed A r11 2, 1970 LEROY .1. .10H/uson hsv. Aitor/rey Sept. 20, 1'971 United States Patent O U.S. Cl. 242--78.1 7 Claims ABSTRACT OF THE DISCLOSURE In uncoiling an open coil of steel strip arranged with its axis vertical and recoiling the strip into a tight coil also arranged with its axis vertical, the strip passes around a vertical tension drum with a vertical snubber roll bearing against the strip on the tension drum in order to position the strip in a desired vertical position. The snubber roll has a spline connection with a rotatable shaft fixed in a Vertical position. Movement of the strip causes rotation of the snubber roll and its shaft. The snubber roll is connected to two diametrically opposed nuts which engage vertical threaded guide rods which are rotated in unison by a reversible motor. If the strip wanders from its desired position the operator runs the motor in the desired position to raise or lower the snubber roll while the coiling continues to return the strip to the desired position.

This invention relates to a method and apparatus for coiling strip and more particularly to the re-coiling of strip which has been annealed 'by open coil annealing. In open coil annealing a coil of steel strip is arranged with its axis vertical and with space between the convolutions of the coil. After annealing it is necessary to Ie-coil the strip to make a tight coil for further processing. This is a common manner of annealing and is described in Wilson et al. Pat. No. 3,114,539 dated Dec. 17, 1963, and in an article entitled Use of Open Coil Process to Change Composition and Improve Sheet Steels which appears on page 73 of the May 1961 issue of Iron and Steel Engineer. In tight coiling, a loose coil of strip is lifted by lowering a magnet supported by a crane on top of the coil with its axis vertical and placed on a turntable around a mandrel. The strip is then threaded around a tension drum having a vertical axis with a snubber bearing against the strip in contact with the tension drum. This snubber may be non-rotatable as shown in the Wilson patent, but it is preferred that it be a rotatable roll as shown in the article and it is to this latter construction that my invention relates. From the tension drum the strip is fed to a take-up turntable and secured to a collapsible mandrel associated therewith. After coiling, the tight coil is removed by the magnet crane. Prior to my invention, the snubber roll could not be vertically adjusted while the coiling operation was in progress. Strips of various widths are coiled on the same equipment and when going from one width of strip to another the vertical position of the snubber roll has to be adjusted since it is desirable that the bottom of the strip be kept at the same elevation regardless of its width and to accomplish this when coiling strip having a good degree of ilatness, the center of the snubber roll should be a short distance above the center line of the strip. The manual adjustment is diicult to make and if too little or too great the coiling operation has to be stopped and the snubber roll position again changed. When the strip does not have a good degree of atness it tends to stray from the desirable horizontal position and it is necessary to move the roll up or down to position the strip properly. Since the strip travels at speeds of 200 to 1200 feet per minute, the change in snubber roll position must be made rapidly to protect the strip from damage and to obtain good coils.

Prior to my invention it was necessary to stop the coiling operation and manually adjust the snubber roll position. Hopefully, the adjustment would be to the proper position; but if not, it was again necessary to stop the coiling and re-position the roll. Thus, during the coiling of a single length of strip it might be necessary to stop the coiling from two to eight times. This, of course, greatly decreased production. In addition, the bottom edge of the strip would be damaged if it dropped too low, and the top surface of the coil was so non-uniform that the edges would be damaged when the magnet was set on it to lift it. In some instances these irregularities would be so great that the magnet would not be able to lift the coil. Thus, a large amount of scrap resulted, and in some instances the entire coil had to be rejected. The adjust- .ment of the snubber roll was in increments so that it was not always possible to position it in the most advantageous location.

It is therefore an object of my invention to provide apparatus which will permit coiling of a strip with its axis vertical with little or no damage to the edges thereof.

Another object is to provide such apparatus which results in increased production. p

A further object is to provide a method of coiling strip which is more effective and accurate than prior methods and may be carried out without stopping the coiling operation.

These and other objects will be more apparent after referring to the following specification and attached drawings, in which:

FIG. 1 is a schematic view including the apparatus of my invention;

FIG. 2 is an elevation, partly in section, of the apparatus of my invention;

FIG. 3 is a view, taken on the line III-III of FIG. 2; and

FIG. 4 is a schematic wiring diagram of the motor control used with my invention.

Referring more particularly to the drawings, reference numeral 2 indicates a turntable for supporting an open coil C with its axis vertical. A collapsible mandrel 4 supports the inside of the coil. The mandrel 4 is connected to drive a generator 6 to provide back tension. Other well known means may be used to provide back tension. Strip S from the coil C passes around a rubber covered tension drum 8 to a recoiling turntable 10 having a collapsible mandrel 12 for receiving the end of strip S. Tension drum 8 is connected to drive a generator 14 and turntable 10 is driven by a motor 16. A snubber roll 18 having a face width substantially less than that of the tension drum is mounted in a housing 20 which is pivotally mounted on a vertical shaft 22. For example, in handling strip of a maximum Width of 72 inches, the drum face is 8O inches and the snubber roll face is 20 inches, plus a two inch reduced diameter portion at each end. An air cylinder 24 moves the housing 20 about the axis of shaft 22 to position roll 18 to exert a desired pressure against the strip S. The snubber roll 18 is rubber covered and is preferably a self-centering roll of the type shown in Lorig Pat. No. 2,772,879 dated Dec. 4, 1956. This roll is rubber covered and has a transverse central slit therein with a plurality of slits on each side thereof extending inwardly from the roll surface toward the adjacent end of the roll. The parts so far described are conventional.

According to my invention I attach brackets 26 and 28 to the housing 20 and secure thrust bearings 30 and 32 to the bottom sides thereof. A thrust bearing 34 is supported on housing 20 below and in vertical alignment with bearing 30, and a similar bearing 36 is mounted on housing 20 below and in vertical alignment with bearing 32. A threaded guide rod 38 is supported in bearings 30 and 34 and a similar rod 40 is support-ed in bearings 32 and 36 with the lower ends extending below the bearings 34 and 36. The rods 38 and 40 each has a reduced diameter lower end so as to provide a shoulder which rests on the associated lower bearing. Sprockets 42 and 44 are secured to the lower ends of rods 38 and 40, respectively. A reversible gear motor 46 drives a sprocket 48 and a chain 50 is passed around sprockets 42, 44 and 48 so as to rotate the rods 38 and 40 in unison. Nuts 52 and 54 are threaded on rods 38 and 40, respectively. The rods 38 and 40 are preferably Beaver No. B-530 ball screws and the nuts 52 and 54 are preferably Beaver ball-screw nuts. A bearing sleeve 56 surrounds snubber roll shaft 58 and is secured to nuts 52 and S4 by means of bracket 58. Bearing housing 60 is secured to the bottom of snubber roll 18 and bearings 62 and 64 are supported by bearing sleeve 56 and bearing housing 60. A key 66 is secured in keyway 68 of shaft 58 and is received in aligned keyways 69 in roll 18 so that the roll 18 and shaft 58 will rotate in unison while permitting vertical movement of roll 18. Any spline connection may be used for this purpose. A generator 70 is connected to and driven by the shaft 58.

Motor 46 receives power from powers lines L1, L2, L3 through forward relay contacts 72C or reverse contacts 74C controlled by relay coils 72 and 74, respectively. Coil 72 is connected to power lines L1, L2 through stop button 76, contact 78C of reverse button switch 78 and contact 80C of reverse button switch 80. Coil 72 also has a locking contact 72C1 in parallel with contact 80C, Coil 74 is connected to power linesy L1, L2 'through stop button 76 and contacts 78C1 and 80C1. Coil 74 also has a locking contact 74C1 in parallel with contact 78C1. This is a conventional control and may include additional safety features. To move the motor 46 in a forward direction stop button 76 is closed, reverse button switch '78 is in the position shown, and forward button 80 is momentarily depressed. This energizes coil 72 to close contacts '72C to move the motor 46 in a forward direction and also closes contact 72C1 to lock the coil 72 in. The button 76 is depressed to stop the motor. To reverse the motor stop button 76 is closed, reverse button 78 is depressed to open contact 78C and close contact 78C1, and forward button 80 is positioned as shown. This energizes coil 74 to close contacts 74C to move motor 46 in reverse and also closes contact 74C1 to lock coil 74 in. The button 76 is depressed to stop the motor.

In operation, the strip S is threaded from the uncoiler turntable 2 to the coiler turntable 10 in the usual manner. The motor 46 is operated to move the snubber roll 18 to a position with its center just above the center of the strip S and the coiling operation then proceeds in the usual manner. However, if the strip moves upwardly or downwardly from its desired position, the operator pushes either switch 74 or 76 to move the roll 18 in the direction to return the strip to its desired position. This is done without stopping the coiling operation, and the operator can readily observe if the movement is too much or too little. As a result of this observation, he again moves the snubber roll 18 up or down if required.

I have found that this method and apparatus greatly reduces edge damage and scrap loss as well as increases production. In one particular mill, it is estimated that a savings of almost $4,000 per month results from decrease in scrap.

While one embodiment of my invention has been shown and described, it will be apparent that other adaptations and modifications may be made without departing from the scope of the following claims.

I claim:

l. In apparatus for coling strip including an uncoiler for supporting a coil of strip with its axis vertical, a

coiler for ceiling said` strip into a tight coil with its axis vertical, a vertical tension drum around which said strip passes in going from said uncoiler to said coiler, a vertical snubber roll arranged adjacent said drum and adapted to bear against the strip passing around said drum, the face width of said roll being less than that of said drum, said snubber roll having an axial opening therethrough, a housing, a vertical roll' shaft supported in said housing and passing through said axial opening, and a drive connection between said shaft and roll permitting vertical movement of said roll; the improvement comprising a pair of vertical guide screws supported by said housing on opposite sides of said roll, a nut mounted on each screw, means connecting said nuts to said roll, and means for rotating said guide screws in unison.

2. The combination of claim 1 in which the means connecting said nuts to said roll includes a bearing housing attached to the bottom of said roll, a bracket attached to said nuts, a bearing sleeve attached to said bracket, and bearing means supported between said bearing housing and sleeve.

3. The combination of claim 1 in which the -means for rotating said guide screws in unison includes a plurality of shafts and a sprocket attached to the bottom of each shaft, a reversible gear motor, a sprocket driven by said gear motor, and a chain passing around said sprockets.

4. The combination of claim 3 in which the means connecting the said nuts to said roll includes a bearing housing attached to the bottom of said roll, a bracket attached to said nuts, a bearing sleeve attached to said brackets, and bearing means supported between said bearing housing and sleeve.

5. The combination of claim 4 including a thrust bearing at the top and bottom of each screw, each screw having a reduced diameter portion extending through said bottom thrust bearing on which the associated sprocket is mounted.

6. The combination of claim 5 in which said snubber roll is a rubber covered seltcentering roll having a transverse central slit thereon with a plurality of slits on each side thereof, each extending inwardly from the roll surface toward the adjacent end of said roll.

7. In the -method of coiling strip in which the strip passes from an uncoiler supporting a coil of said strip arranged with its axis vertical around a vertical tension drum to a coilerV having a vertical axis with a snubber roll bearing against the strip on the tension drum; the steps comprising positioning the strip at a desired vertical location on said tension drum, positioning said snubber roll with its transverse center a short distance above the longitudinal center of said strip, continuously moving said strip longitudinally, raising said snubber roll while continuing said longitudinal movement of said strip when the strip drops below its desired vertical location, and lowering said snubber roll while continuing said longitudinal movement of said strip when the strip rises above its desired vertical location.

References Cited UNITED STATES PATENTS 3,008,663 ll/ 1961 Blackman 242-78.1X

FOREIGN PATENTS 941,350 11/1963 Great Britain 242--78.1

GEORGE F. MAUTZ, Primary Examiner E. J. MCCARTHY, Assistant Examiner -U.S. Cl. X.R. 226--179 

